Aircraft Quiz #41

DougRobertson

Name the aircraft that had about a 15 year gestation period because it had to be supersonic at low altitudes AND reach above Mach 2 flight at high altitudes AND was first aircraft to use integrated circuits AND it had to operate STOL. Early versions' low altitude flights were dangerous and total losses were high. (Probably more clues than I have ever given).

1. Country of origin.

2a. Year of first studies of the design? 2b. Design nomenclature? 2c. Builder?

3a. Official nomenclature of first production version? 3b. Variants?

4a. Date of first flight? 4b. Service ended what year?

5. What aircraft did it displace?

6a. In-service engine nomenclature? 6b. What engine was this derived from and then built under license with the in-service nomenclature?

Some wrongly called it a "Biplane." I am NOT putting you on

moxy

1. Sweden. They like their fighters to be able to operate from normal tarmac roads

away from airfields hence the requirement for some STOL capability.

2a. 1952 2b. Viggen 2c. SAAB

3a. AJ37 3b., SU37 / SF37 / SK37

4a. 8/2/1967 (That's the eighth of February in England) :)

4b. Retired from Front Line Nov 2005. Last official service flight June 2007

5. Saab Lansen (Attack Role) Saab Draken (Fighter Role)

6a. Volvo RM8B Afterburning Turbofan

6b. Pratt & Whitney JT8D. This engine was used in B737-100 and -200 models.

moxy

If I'm correct Doug, it was the reference to a biplane that made me go for a high performance aircraft with a canard wing. Also, having been to Sweden, the STOL requirement reminded me of seeing reinforced public roads that could be used by fighters in times of war.

DougRobertson

Gee Rob, and here I thought my biplane reference would put you off the trail to correct answers! Congratulations, Again!

Here are mine.

1. Sweden

2a. 1952. 2b. Viggen System 37 air defense network (airborne component of). 2c. SAAB

3a. AJ 37 Viggen. 3b. SF 37, SH 37, SK 37 (two seats), final production JA 37.

4a. Feb. 8, 1967. 4b. 2007.

5. The SAAB Lassen and the SAAB Draken.

6. This question admittedly not well posed. My apologies. The final JA 37 Viggen version used one modified Volvo Flygmotor RM8B Turbofan with after-burning which was a license-built adaptation of the P&W JT8D with the USA providing advanced engine technology agreements. Early Viggens used the modified Volvo RM8A version of the JT8D with less power.

The Viggen (Thunderbolt or Tufted Duck) depending on interpretation of the word Viggen, was an advanced for its time aircraft used for many roles-air superiority, close air support, reconnaissance, and maritime surveillance for over 30 years in service. Requirements were: supersonic low altitude flight, Mach 2 high-altitude flight, unprecedented STOL capability including operation on primitive roadways and to be simple to service by inexperienced ground crews. Early versions were dangerous with 40 lost of total of all versions-149 built.

To meet these extreme requirements the Viggen design had a then-unconventional delta-wing configuration with two-section elevons, foreplane fixed-canard with trailing-edge flaps, tandem main wheel tri-gear. Thrust reversers and the tandem undercarriage allowed short, non-flare landings after early landing problems on damaged runways/roads-(a design requirement). Early version was underpowered, hence the RM8B version engine. The last operation date I have for the Viggen is 2007. Swedish policy: No foreign sales.

Specs for JA 37 Viggen

Power: one Volvo RM8B turbofan 16,203 lb thrust, with afterburning 28,108 lb thrust.

Max speed: at altitude above Mach 2,or more than 1,145 kts, at 330' max speed Mach 1.2

Cruise speed: 600 mph

Time to climb to 32,800'-less than 1 min, 42 sec.

Weight loaded: 37,348 lb

Max range: 1,200 miles with internal fuel

Wingspan: 34'9"

Length overall with probe: 53'10" Fuselage: 51'2"

Height: 19'4"

Wing area: 495.1 sq ft

Armament

One 30mm Oerlikon KCA-cannon

Either six AIM-9 Sidewinders or two RB71 Skyflash and four AIM-120 AMRAAMs or four rockets.

moxy

Thanks for the additional information Doug. As a matter of interest I took the attached Photo at the Aviodome Museum, Lelystad, Holland.

DougRobertson

Thank you Rob, for the great photo of a SAAB Viggen. It clearly shows the unusual for its time aeronautical design elements. Photos always add to the quiz value and interest here.